1. Field of the Invention
The disclosures herein generally relate to an image forming apparatus, a control method and a storage medium. Especially, the present invention relates to an image forming apparatus provided with a data transfer function according to direct memory access control for image data between various types of memories connected to various types of devices, such as an engine ASIC (Application Specific Integrated Circuit), a controller ASIC or a processor, a control method for transferring the data for image formation processing and a storage medium.
2. Description of the Related Art
Conventionally, an image forming apparatus with a specification of multifunction peripheral (MFP), i.e. a digital multifunction peripheral, in which plural functions, such as a printer function, a copying function, a scanner function or a facsimile function are combined into a single chassis, is generally configured so that an engine ASIC is connected to a controller ASIC and instruction control for image formation processing is performed from a processor (CPU: central processing unit), which controls an entire apparatus connected to the controller ASIC, via the controller ASIC. For example, a configuration has been known, in which the controller ASIC and the engine ASIC are connected via a PCI interface, a PCI Express (hereinafter, referred to as PCIe) interface or the like, and the controller ASIC and the processor are directly connected by the PCIe interface or connected via a chipset.
Related art for the well-known art area includes, for example, Japanese Published Patent Application No. 2008-310798, disclosing an image processing controller and an image forming apparatus, in which a data transfer path using both PCI interface and PCIe interface can be controlled.
In the related art described in Japanese Published Patent Application No. 2008-310798, in order to improve data transfer performance for image data among the engine ASIC, the controller ASIC and the processor (CPU), availability is enhanced by providing plural interfaces including a PCI interface and a PCIe interface, and the data transfer path using the plural interfaces, such as the PCI interface and the PCIe interface can be controlled. However, a control means for the data transfer path does not take account of priority, so that when the data transfer of image data by the direct memory access control is performed among various types of memories connected to the engine ASIC, the controller ASIC and the processor, the data transfer is not always performed efficiently. Accordingly, there is a problem that a transfer band for other data transfer with higher priority is often reduced.